#include <stdio.h>

#define M 1234

int main()
{
    printf("hello world1\n");
    printf("hello world2\n");
    printf("hello world3\n");
    printf("hello world4\n");
    printf("hello world5\n");
    printf("hello world6\n");
    printf("hello world7\n");
    printf("hello world8\n");
    printf("hello world9\n");
    printf("hello world0\n");
#ifdef SHOW 
    printf("Hello show!\n");
#else 
    printf("Hello undef\n");
#endif 
    
    printf("宏:%d\n",M);
    return 0;
}
